The invention generally relates to yttrium oxide based phosphor powders. More particularly, the invention relates to a method for making the yttrium oxide based phosphor powders having high efficiency.
Yttrium oxide with europium doping (also known as “YEO”) is a well-known phosphor composition. A YEO phosphor composition emits red light when it is irradiated by certain high-energy radiation having wavelengths below the visible range. This property is advantageously used on an industrial scale, for example, in trichromatic fluorescent lamps, backlighting systems for liquid crystal displays and in plasma systems.
Various synthesis methods have been developed to maximize the efficiency of YEO phosphor. Some of the synthesis methods improve crystallinity of the phosphor thereby enhancing the efficiency. Some other synthesis methods optimize the particle size distribution and morphology of phosphor particles in order to get a uniform coating during lamp coating.
However, a demand for a simple and cost effective method of forming crystalline YEO with better size and microstructure distribution and having high efficiency is an unmet need. The present invention is directed towards a simple method of forming higher efficiency YEO powders.